function [X_dot] = plant_qua(x, F_plant, M_plant)
global g  m_p1
global a1_p a2_p a3_p
global b1_p b2_p b3_p

X_dot = zeros(12,1);

Ux = cos(x(1))*sin(x(3))*cos(x(5))+sin(x(1))*sin(x(5));
Uy = cos(x(1))*sin(x(3))*sin(x(5))-sin(x(1))*cos(x(5));

% 无人机的位姿信息
X_dot(1) = x(2);
X_dot(2) = x(4) * x(6) * a1_p + M_plant(1) * b1_p;
X_dot(3) = x(4);
X_dot(4) = x(2) * x(6) * a2_p + M_plant(2) * b2_p;
X_dot(5) = x(6);
X_dot(6) = x(2) * x(4) * a3_p + M_plant(3) * b3_p;

% 位置状态
X_dot(7)  = x(8); 
X_dot(8)  = Ux * F_plant/m_p1;
X_dot(9)  = x(10);
X_dot(10) = Uy * F_plant/m_p1;
X_dot(11) = x(12);
X_dot(12) = - g + cos(x(1)) * cos(x(3)) * F_plant/m_p1;
end 